E. Pierce Marshall dies suddenly

Marshall was 67 when he died Tuesday in Dallas while battling an infection, family spokesman David Margulies told the Los Angeles Times.

Marshall gained national attention during his legal dispute with Smith.

Smith was 26 when she married 89-year-old J. Howard Marshall II in 1994. She claimed he promised her a large portion of his $1.6 billion estate before he died and alleged the younger Marshall has lied and forged documents to prevent her from getting the money.

A legal battle is ongoing but there is no word on how Marshall's death will affect it.

Smith's attorney conveyed condolences to the family and refused to comment any further.

Marshall oversaw his family's estate and sat on the board of commodities giant Koch Industries Inc., which runs oil refineries and pipelines, among other endeavors.